I had the same trouble.
I found at idle there was no airflow on the condenser for the A/c out front, as the job of the condenser is to remove heat from the interior and with no air the condenser cannot do its job. The fan clutch to save fuel economy, only works when the engine radiator is hot AND air flow is moving over the clutch. So with a car sitting idle, the fan clutch will not kick in either as the air from the radiator is not moving enough heat over the fan clutch to kick in.
Basically I added a electric fan in front of the A/c condenser with a thermostat attached to the condenser set for 160 degrees. Now when ever I come to a red light after about 10 seconds the electric fan kicks in and I have ice cold air at a traffic light. When I take off from the light the fan shuts off after about 20 seconds due to the engine fan kicking in. The first Ford dealer told me I had a leak and sold me a 250 dollar hose, still hot and they said the same hose was leaking again so they wanted me to bring it back in again to change that hose. I went to another Ford dealer and they told me I needed a $400 dollar fan clutch. I'm glad I am a mechanic myself otherwise I still would be sitting in a hot cab & out 4 bills. My old fan clutch works fine once hot air passes over it (like it is designed to do). Just drove it out to Houston in 100 plus degree weather a couple of weeks ago, temp gauge never moved off normal. A/C was cold all day long. AutoZone 12" fan with adjustable thermostat will solve your problems.
Originally Posted by Tschro
Hi guys, I have a 2002 screw with the 4.6l that has 194k on it. The A/C works fine as long as the truck stays moving. When you stop/idle the compressor kicks off and it blows warm air for a few minutes then the compressor kicks back on and cool air eventually comes out( but much more hot air than cool air while idling). I bought a gauge and some freon at Wallyworld today and the gauge says I do not need to add any more R-134a. Anyone have any ideas? One of the posts said fan clutchmight be a possibility but I did stick a rolled up newspaper into the fan and it was shredded instantly. Thanks in advance